Anal. Chem. 1906, 58,1037-1042
1037
Surface Properties of Electrochemically Pretreated Glassy Carbon Tsutomu Nagaoka* and Takashi Yoshino Department of Applied Chemistry, Yamaguchi University, Tokiwadai 2557, Ube 755, J a p a n
The surface properties of electrochemically treated glassy carbon were examined by cyclic voltammetry. The surface structure became very porous by treatment. Protons and catechol (1,2dihydroxybenzene) could dlffuse Into the pores, and the surface area estimated from voltammetry for these species was much larger than that for ferrlcyanlde. I n the voltammograms of catechol, two major symmetric peaks were observed for the treated electrodes, and they were asslgned to catechol adsorbed on the surface and the mlcropore surface. However, relative sizes of molecules were not important to adsorptlon on the mlcropore surface, because other similar compounds did not show such adsorption. Carbonyl groups were Introduced onto the surface to study the stoichiometry between adsorbed catechol and these groups.
pretreated surface from the results of the surface modification with o-phenylenediamine and of phase-sensitive ac voltammetry (12). Hu, Karweik, and Kuwana found by X-ray PES that there was nitrogen only on the modified surface and also concluded that o-quinones are likely candidates as the functional groups (13). Elsewhere, one of the present authors (T.N.) studied the specific interaction between 1,4-benzoquinone and the glassy carbon surface, which was polished with alumina only, at low temperatures (
